Abstract: A helicopter includes missile storage means (29) adapted to store a plurality of missiles (26) laterally within a fuselage (28) and missile launcher means (40) located at the end of a lateral outrigger (27) for pivotal movement about a generally vertical axis (42) between a loading position generally laterally of the fuselage and a launch position generally parallel with a longitudinal centreline of the fuselage. In the illustrated embodiment, the launcher means comprises an elongated support beam (45) for selective engagement by a longitudinally extending tubular member (32) attached to each missile and includes transfer means (51, 52, 60, 61) for transferring a missile between the storage means and the launcher means when the latter is in said loading position.

Abstract: This invention relates to a method and apparatus for reducing vibration of a helicopter fuselage. The apparatus comprises a plurality of actuators interconnecting parts of the helicopter structure capable of relative motion at an exciting frequency, means to continuously oscillate the actuators at a frequency corresponding to the exciting frequency, a plurality of accelerometers attached to the fuselage for generating signals representative of fuselage dynamic accelerations, and processing means for processing said signals and providing output signals for controlling the phase and magnitude of operation of the actuators. In a described embodiment, one of the relatively movable parts comprises a raft structure carrying the gearbox and engines and attached to the fuselage by a resilient attachment adjacent each of its four corners.

Abstract: A helicopter (10) has a fuselage (11) provided with storage means (19, 20, 24) for storing a plurality of missiles (16) longitudinally of the fuselage, reloadable turret means (17) beneath the fuselage for movement in azimuth and elevation and transfer means (20b, 21) for transferring a missile from the storage means to the turret means. In the illustrated embodiment the missiles are stored externally of generally vertical side walls (13) and a lower generally horizontal wall (14) of the fuselage and fairings (39) are provided to protect the externally mounted missiles.

Abstract: A fuel flow control valve is adapted to control the flow of fuel in a spill line to control the amount of fuel usable in a two speed gas turbine. The valve includes fluid pressure operated valve means controlled by two variable volume fluid pressure chambers to provide appropriate fuel flow for `run` and `idle` conditions, and positioning means to automatically position the fluid pressure operated valve means when the control valve is at rest to provide a flow of fuel appropriate for `start-up` of the gas turbine that is greater than the flow required in the `idle` condition but less than that required in the `run` condition. Operating fluid pressures connected to the chambers may comprise either gaseous fluid pressures tapped from a stage of the compressor of the gas turbine or a combination of said gaseous pressure source and a liquid fluid pressure source preferably comprising a fuel pressure supply tapped from the fuel supply line to the gas turbine.

Abstract: A pallet (12) for an automated transportation apparatus includes resilient restraining means (14) protruding from an upper load carrying surface (13) to prevent sliding movement of an article on the surface.

Abstract: A helicopter rotor includes a plurality of rotor blades attached to a rotor hub by flexure members adapted during operation to permit pitch changes and flap and lag movements of the rotor blades. Each flexure member comprises a plurality of longitudinally extending reinforcing plates which in cross section extend generally radially from a geometric center of the flexure member and are enclosed in a resilient matrix material.

Abstract: An outboard region of a helicopter rotor blade of aerofoil cross section has a thickness to chord ratio not greater than twelve percent and an inboard region has a thickness to chord ratio greater than twelve percent. Preferably, the thickness to chord ratio of the inboard region is greater than eighteen percent and may increase towards the root end to about twenty four percent. The inboard region may extend outwardly to a position not exceeding sixty percent of an operating radius of the rotor blade.

Abstract: A recirculating lubricating system includes a monitor filter unit (16) between a pump (13) and a main filter element (17). The monitor filter unit (16) includes diverting means (23, 31) to ensure that a proportion of the oil flowing between the pump and the main filter element is diverted through a removable monitor filter element (28).

Abstract: A bearingless helicopter rotor includes an integral damper and pitch change assembly (16) adapted to damp lead/lag movements of a rotor blade and to change the pitch of the rotor blade. In described embodiments, the assembly includes a generally tubular body portion (17, 27) closed at one end and attached by torque transmitting means (18, 28) to a flexure member blade attachment and a rod (20, 29) protruding axially from the other end of the body portion and attached adjacent the rotor hub. Pitch change movements are effected by rotation of the body portion about its longitudinal axis and damping of lead/lag movements either by metering of an incompressible medium across a piston (23) in a chamber (24) formed internally of the body portion or by an annular body of elastomer material (34) bonded to the outside diameter of the rod and the inside diameter of the body portion.

Abstract: A composite helicopter fuselage comprises at least one main frame member having two generally vertical side beams joined by generally horizontal top and bottom beams. Each side beam comprises a top hat section bonded to a filler material and the top and bottom beams each comprise two channel sections arranged back to back and bonded to a filler material. An area at each end of the top and bottom beams is devoid of filler and the top hat sections of the side beams are slotted between the channel sections, the parts then being joined by bonding the internal surfaces of the channel sections to the external surfaces of the top hat sections. The fuselage is completed by panels attached to the external flanges of the side and top and bottom beams.

Abstract: An aircraft seat (11) particularly adapted as a pilot seat for a helicopter includes a seat bucket (12) having a back-rest portion (13) supported by an articulated support structure (14) adapted to react vertical, longitudinal and lateral loads and to permit normal vertical stroking of the seat by extension of any energy absorber (32) in the event that the support structure becomes mis-aligned in a hard landing. The structure comprises two parallel generally vertical guide tubes (15a, 15b). The lower ends of both guide tubes are attached to a cabin floor (17) by universally pivoted joints (18), the upper end of a first one of the guide tubes (15a) is pivotally attached to one end of a generally horizontal straight link (20) to react longitudinal loads only and the upper end of the second guide tube (15b) is pivotally attached at the apex of a generally horizontal triangular link (21) so as to react both lateral and longitudinal loads.

Abstract: A helicopter rotor includes attachment means for attaching a rotor hub to a tubular rotor drive shaft in a manner establishing a primary thrust load path and further attachment means adapted to provide a normally passive secondary thrust load path and operative automatically to retain the rotor hub in the event of a failure in the primary thrust load path. In the described embodiments the further attachment means comprise a multi-part collet consisting of a plurality of identical collet parts located internally of the drive shaft. Each collet part has an external frusto-conical surface one end for location adjacent a mating surface formed internally of the drive shaft, and a radially extending flange portion at its other end for attachment to an end surface of the drive shaft.

Abstract: A portion of the surface area of a resin bonded structure comprises an exposed dimpled electrically conductive metal shim bonded to the structure to provide a low electrical impedance connection for mounting a device such as a radio antenna. Preferably, a ply of unidirectional carbon fibres coated with an electrically conductive material such as a uniform and concentric coating of electroplated nickel is located between the shim and the outer carbon fibre layer of the structure with the fibre orientation of the ply of coated carbon fibres at 90 degrees to the carbon fibre layer. The invention also extends to a method of providing a low electrical impedance connection on to a pre-cured resin bonded carbon fibre structure and to a method of attaching a radio antenna on to such a structure.

Abstract: Diametrically opposed rotor blades of a helicopter rotor are interconnected by a strap member which is flexible in torsion and in a plane perpendicular to a plane of rotation and has a plan profile extending between leading and trailing edges. Each rotor blade is provided with inwardly extending lever means adapted for attachment to drive means externally of the strap plan profile and adjacent one of its edges and to pitch control means externally of the plan profile and adjacent the other of its edges. In one embodiment, the lever means comprise individual levers formed integral with a connecting member rotationally fixed to the rotor blade and in a further embodiment the lever means comprise an inwardly extending torque sleeve. The drive means attachments of opposed blades lie along a common axis parallel to the plane of rotation and intersecting the axis of rotation at approximately 45 degrees to a longitudinal axis of the strap member.

Abstract: A helicopter transmission system includes a gearbox comprising a gearcase (11) having a hollow stub axle (12) by which operational loads are transmitted from a main sustaining rotor to a fuselage structure. One or more input speed reducing gear trains (20, 21, 22, 23) are individually supported in hollow lobe portion(s) (14) supported from the axle (12), the or each lobe portion having an individual lubricating oil sump (18) and circulating means (31) adapted to circulate lubricating oil to the respective gear trains. Preferably, interconnecting means (33) are provided to connect the respective individual sumps, and valve means (32, 35) are adapted to maintain a flow of lubricating oil in the event of a loss of oil from one of the sumps.

Abstract: A helicopter transmission system is disclosed in which drive from three engines is transmitted to two output channels each of which is divided by dividing means to drive two output pinions meshed with a common combining gear rotationally fixed to a sustaining rotor drive shaft. Balancing means are provided to balance the torque transmitted by the respective pairs of output pinions and, in the described embodiment, the balancing means comprise a plurality of meshing spur gears arranged with one of the spur gears drivingly connected to one of the engines and a further two of the spur gears are drivingly connected respectively to the two output channels. Conveniently, a further one of the spur gears provides a power take off to an anti torque rotor drive shaft.

Abstract: A helicopter rotor (10, 29) includes a rotor hub (11, 30) supporting a plurality of rotor blades, and a pitch control means comprising a universal joint (21, 45) adapted to permit both tilting and axial vertical movements of the control means to change the pitch of the rotor blades both cyclically and collectively. The universal joint has three radially extending pins (22) each supporting a radially slidable and rotatable bearing (23) having a spherical external surface (25), the bearings being located in generally axially extending tracks (26) having a circular cross-sectional shape for rolling engagement by the bearings.Axial movements are permitted by rolling of the bearings along the tracks and tilting movements by a combination of rolling and a sliding movement of the bearings along the pins.Several embodiments are described and illustrated.

Abstract: A stores handling apparatus for moving and positioning stores relative a parked aircraft to facilitate loading thereof comprises a beam member (21) having releasable coupling means (22) near each end for attachment of at least one stores carrying trolley (23) and so that each trolley projects substantially parallel to the beam member. Means such as rollers (24) or wheels (33) provide for movement of the beam member along a surface, and guide means (25) are adapted in operation for engagement with guide means (39) formed in a trackway (38) on the surface.In operation, the stores handling apparatus is used in combination with an aircraft moving apparatus operable to align an aircraft on the trackway and, preferably, of a type comprising a trolley (50) movable along the same trackway.The apparatus and system of this invention is particularly suited for use in the moving and positioning of stores relative an aircraft parked on the deck of a ship.

Abstract: A helicopter rotor having a rotor hub and a plurality of rotor blades includes for each blade a blade fold mechanism comprising a reversible rotary power source and a rack and pinion mechanism adapted to operate one or more lock pins and to fold the blades between an operational spread position and a folded position. Two embodiments of the invention are described and illustrated.

Abstract: A connecting element having end regions (22, 23) joined by an intermediate by an intermediate region (26) is constructed of a plurality of fibre filaments extending longitudinally and continuously throughout its length. The fibers in the end regions are embedded in a thermo-setting resin matrix material and the fibres in the intermediate region are embedded in a resilient matrix material thereby permitting relative resilient torsional movement of the end regions about a longitudinal axis. Such a connecting element is particularly suited for use in a helicopter rotor and several embodiments are described and illustrated. In all embodiments the torsional flexibility of intermediate region (26) provides for blade feathering movements and in a preferred embodiment the inner end region (22) is constructed so as to be resiliently flexible in a blade flap plane and the outer end region (23) is constructed so as to be equally resiliently flexible in the blade flap and lead/lag planes.